EBC Brakes CFA647 Disc Brake Pads Compatible with Hope 3/4/RX4/E4 Red – Organic (Soft)EBC CFA647 DISC BRAKE PADSCompatible with Hope Brake systems; * E4 * Race Evo E4 * RX 4-SH * RX 4-SR * RX4+ (FM +20) * RX4+ (FM) * RX4+ (FMF +20) * RX4+ (PM) * Tech 3 E4 * Tech 4 E4*Other systems may be compatible (list accurate as of Sept. 2020)GREEN – ORGANIC (STANDARD)Designed for general use including Road Cross-Country and Trekking. Medium/soft pad compound for better stopping. This is a resin pad made of an organic compound. Can be used on hardened or non-hardened rotors. Medium lifetime pad for all conditions.RED - ORGANIC (SOFT) * Ideal for Downhill & Racing * Minimum heat transfer to hydraulic systemImproved Brake or Race Use Higher friction red compound improves brake effect and breathes life into a dull system. These pads offer more grip than standard and can be used as an upgrade pad for any system where stopping power needs a boost. Also due to the low heat generation red pads are ideal for downhill racing.GOLD - SINTERED COPPER * Most powerful braking of any pad material * Massive lifetime pad for hardened discs only * Sintered copper construction * Great for long-life cross-country use * Not recommended for downhill racingThese USA made sintered copper pads will last longer and brake stronger than anything you can buy. Do NOT use these on discs marked RESIN pad as such discs will be UNHARDENED steel and these pads could damage soft materials.